Radiative and Non-Radiative Decay Pathways in Carbon Nanodots toward Bioimaging and Photodynamic Therapy
The origin and classification of energy states, as well as the electronic transitions and energy transfers associated with them, have been recognized as critical factors for understanding the optical properties of carbon nanodots (CNDs). Herein, we report the synthesis of CNDs in an optimized proces...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-12-01
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| Series: | Nanomaterials |
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| Online Access: | https://www.mdpi.com/2079-4991/12/1/70 |
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| author | Yujin Kim Yoonsang Park Seulgi Han Wonchan Park Mungu Kim Kyunghwan Kim Jinmyoung Joo Sei Kwang Hahn Woosung Kwon |
| author_facet | Yujin Kim Yoonsang Park Seulgi Han Wonchan Park Mungu Kim Kyunghwan Kim Jinmyoung Joo Sei Kwang Hahn Woosung Kwon |
| author_sort | Yujin Kim |
| collection | DOAJ |
| description | The origin and classification of energy states, as well as the electronic transitions and energy transfers associated with them, have been recognized as critical factors for understanding the optical properties of carbon nanodots (CNDs). Herein, we report the synthesis of CNDs in an optimized process that allows low-temperature carbonization using ethanolamine as the major precursor and citric acid as an additive. The results obtained herein suggest that the energy states in our CNDs can be classified into four different types based on their chemical origin: carbogenic core states, surface defective states, molecular emissive states, and non-radiative trap states. Each energy state is associated with the occurrence of different types of emissions in the visible to near-infrared (NIR) range and the generation of reactive oxygen species (ROS). The potential pathways of radiative/non-radiative transitions in CNDs have been systematically studied using visible-to-NIR emission spectroscopy and fluorescence decay measurements. Furthermore, the bright photoluminescence and ROS generation of these CNDs render them suitable for in vitro imaging and photodynamic therapy applications. We believe that these new insights into the energy states of CNDs will result in significant improvements in other applications, such as photocatalysis and optoelectronics. |
| first_indexed | 2024-03-10T03:28:32Z |
| format | Article |
| id | doaj.art-00f8ffd3a8664c5eb56ec40a90262ada |
| institution | Directory Open Access Journal |
| issn | 2079-4991 |
| language | English |
| last_indexed | 2024-03-10T03:28:32Z |
| publishDate | 2021-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Nanomaterials |
| spelling | doaj.art-00f8ffd3a8664c5eb56ec40a90262ada2023-11-23T12:01:04ZengMDPI AGNanomaterials2079-49912021-12-011217010.3390/nano12010070Radiative and Non-Radiative Decay Pathways in Carbon Nanodots toward Bioimaging and Photodynamic TherapyYujin Kim0Yoonsang Park1Seulgi Han2Wonchan Park3Mungu Kim4Kyunghwan Kim5Jinmyoung Joo6Sei Kwang Hahn7Woosung Kwon8Department of Chemical and Biological Engineering, Sookmyung Women’s University, Seoul 04310, KoreaDepartment of Chemical and Biological Engineering, Sookmyung Women’s University, Seoul 04310, KoreaDepartment of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, KoreaDepartment of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, KoreaDepartment of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, KoreaDepartment of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, KoreaDepartment of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, KoreaDepartment of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, KoreaDepartment of Chemical and Biological Engineering, Sookmyung Women’s University, Seoul 04310, KoreaThe origin and classification of energy states, as well as the electronic transitions and energy transfers associated with them, have been recognized as critical factors for understanding the optical properties of carbon nanodots (CNDs). Herein, we report the synthesis of CNDs in an optimized process that allows low-temperature carbonization using ethanolamine as the major precursor and citric acid as an additive. The results obtained herein suggest that the energy states in our CNDs can be classified into four different types based on their chemical origin: carbogenic core states, surface defective states, molecular emissive states, and non-radiative trap states. Each energy state is associated with the occurrence of different types of emissions in the visible to near-infrared (NIR) range and the generation of reactive oxygen species (ROS). The potential pathways of radiative/non-radiative transitions in CNDs have been systematically studied using visible-to-NIR emission spectroscopy and fluorescence decay measurements. Furthermore, the bright photoluminescence and ROS generation of these CNDs render them suitable for in vitro imaging and photodynamic therapy applications. We believe that these new insights into the energy states of CNDs will result in significant improvements in other applications, such as photocatalysis and optoelectronics.https://www.mdpi.com/2079-4991/12/1/70carbon dotnear-infraredreactive oxygen speciesbioimagingphotodynamic therapy |
| spellingShingle | Yujin Kim Yoonsang Park Seulgi Han Wonchan Park Mungu Kim Kyunghwan Kim Jinmyoung Joo Sei Kwang Hahn Woosung Kwon Radiative and Non-Radiative Decay Pathways in Carbon Nanodots toward Bioimaging and Photodynamic Therapy Nanomaterials carbon dot near-infrared reactive oxygen species bioimaging photodynamic therapy |
| title | Radiative and Non-Radiative Decay Pathways in Carbon Nanodots toward Bioimaging and Photodynamic Therapy |
| title_full | Radiative and Non-Radiative Decay Pathways in Carbon Nanodots toward Bioimaging and Photodynamic Therapy |
| title_fullStr | Radiative and Non-Radiative Decay Pathways in Carbon Nanodots toward Bioimaging and Photodynamic Therapy |
| title_full_unstemmed | Radiative and Non-Radiative Decay Pathways in Carbon Nanodots toward Bioimaging and Photodynamic Therapy |
| title_short | Radiative and Non-Radiative Decay Pathways in Carbon Nanodots toward Bioimaging and Photodynamic Therapy |
| title_sort | radiative and non radiative decay pathways in carbon nanodots toward bioimaging and photodynamic therapy |
| topic | carbon dot near-infrared reactive oxygen species bioimaging photodynamic therapy |
| url | https://www.mdpi.com/2079-4991/12/1/70 |
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